The role has been created following a merger of the communications and culture departments last year.
Keir heads a 12-strong comms team, which includes the press office and internal marcoms, as well as a 30-strong galleries and museums function.
He said his priorities included improving public consultation and promoting the culture of the city, which unsuccessfully bid to become European Capital of Culture in 2008.
Although not selected the council has continued to invest in cultural activities, Canterbury has recently attracted more than POUND SIGN 750,000 in grants for its 'Make It Real' cultural programme over the next 18 months.
Another task will be to promote work being carried out by the council to improve community safety following a recent consultation over residents' concerns.
'The survey of residents found that a major issue for them was crime and disorder,' he said. 'This kind of communication with residents is vital.'
Keir reports to culture and communications director Janice McGuinness and takes the role after ten years at Saatchi & Saatchi, where he was managing director of its new media division and worked with clients including Procter & Gamble and Visa International.
The Make It Real programme is billed by the council as the biggest single programme of arts the district and its east Kent partners has ever seen.
Funding comes from the Urban Cultural Programme, a one-off lottery initiative combining funding from the Millennium Commission and Arts Council England.